Real Real Photo Cards

[Dave43]

i was looking thru my real (glossy) photo cards of London and arrived at the following tentative conclusions but I'm lost without a copy of Picture Postcards & their Publishers by Anthony Byatt.
the technology and the printers may have been German but these are publishers and I repeat LONDON postcards
Davidson Bros, London & New York seem to be early on the scene, lots of Franco British Exhibition (1907/8) many are "framed" (I don't like frames!) 5,000 series but I have nothing later, did they go under?
After them there's a whole lotta people
Phillip Hunt & Co. published cards under their own name and for Wm Whiteley, Selfridges, WH Smith
5000 series for WHS 1921, others numbered 11,000 and 28,000
Rotary Photo Co, originally Ltd registered 1898, went into voluntary liquidation 1916 struck off 1923 but seemed to carry on trading into the 1940's? published for WHS as well, had works at West Drayton?
10,000 series is London, I've seen 6,000 for Crystal Palace, 3,000 is shipping, 4,000 actors and actresses, 9,000 similar but bookmark shape. my cards date from c 1909-1914
Art & Humour Chancery lane, WC2 c1921
Anonymous 1925-1935
DF & Son London I assume are D Freedman & Son Mansell St EC was there some tie up with Rotary or did they take them over? I have 2 cards with identical pics and numbers to Rotary, one dated as late as 1945.
Photochrom Tunbridge Wells started early and went on a long time
Any thoughts?